Cosmetic stick preparations, such as lipsticks or deodorant sticks, have been known for quite some time and are used regularly by many consumers in the widest fields of body care.
However, they may have the disadvantage that they are perceived as being too hard when applied to the skin. Other problematic aspects are at times the dosing of the products and the undesirable tendency of some stick preparations to form residues on the application surface.
For these reasons, what are known as “soft solids” were developed as a further form of application, which are perceived to be more pleasant by many consumers than stick preparations.
“Soft solids” are understood to mean viscous compositions that typically have a creamy texture and, prior to use, are usually pushed out through one or more openings of a dispensing device of the applicator. During this process, pressure is exerted on the composition, under which the formulation often becomes unstable and expels one of the liquid components thereof. This phenomenon is referred to as syneresis and can typically be observed with soft solids having a high oil content.
Products that exhibit syneresis of >8% at 50° C. are already problematic and undesirable.
Anhydrous soft solids and anhydrous stick preparations typically include suspensions of one (or more) auxiliary substance(s) and/or active ingredient(s) in a nonpolar oil, which includes at least one thickening agent to prevent sedimentation of the auxiliary substance(s) and/or active ingredient(s). It was found that multiple commercially known thickening agents (thickening agent systems) favor this undesirable syneresis, in particular when the preparations, as described above, are pushed out of the applicator by the exertion of pressure (soft solids).
It was therefore the object of the present invention to provide a cosmetic composition in the form of an anhydrous composition as a soft solid, which exhibits no, or at least reduced, syneresis. Moreover, the composition is to have the necessary hardness and texture so as to be easily distributed on the skin.
A necessary hardness shall preferably be understood to mean a hardness of 0.015 to 0.045 mN, more preferably of 0.016 to 0.044 mN, particularly preferably of 0.017 to 0.043 mN, and in particular of 0.018 to 0.042 mN.
Reduced syneresis shall preferably be understood to mean syneresis of <7.5%, more preferably <7.25%, particularly preferably <7%, and in particular <6.75%.
Finally, the composition should not leave behind a sticky sensation on the skin and no residues on textiles after application.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.